Douglas Durian

My general research interests are in the area of soft matter physics: the structure, dynamics, and macroscopic behavior of a very broad class of materials that are typically noncrystalline and composed of macromolecules (e.g. polymers, liquid crystals, surfactants, biomolecules) or particulates (e.g. nanoparticles, colloids, grains, bubbles, droplets). This growing field complements solid state and statistical physics and has considerable overlap with disciplines of chemistry, geology, chemical and mechanical engineering, materials science, and even biology. A common theme in soft condensed matter is that while the materials are disordered at the molecular scale and homogeneous at the macroscopic scale, they usually possess a certain amount of order at an intermediate, or mesoscopic, scale due to a delicate balance of interaction and thermal or driving effects. The general goal is to determine this structure and its dynamics, how it arises, and how it influences the macroscopic behavior. This is obviously of great practical interest since almost all matter we encounter in our everyday lives is a form of soft condensed matter. This is also of great fundamental interest since while we understand the physics controlling the behavior of individual atoms and molecules, and the physics controlling the behavior of macroscopic chunks of matter, we are relatively ignorant of the complex connection between these well known limits. Therefore, completely new and unexpected behavior often arise, which we enjoy discovering and quantifying experimentally and modeling theoretically. Since the mesoscopic structure of many forms of soft condensed matter strongly scatters visible light, they appear opaque. My research takes advantage of this multiple light scattering property, as well as digital video imaging, to probe mesoscale structure and dynamics. Recent focus is on particulate systems composed of colloids, grains, or bubbles, which are all typically far-from-equilibrium and exhibit non-linear response and unusual collective behavior near jamming.